A lift with a double-deck cage is known from WO 98/09906 in which the upper deck can be matched to the upper edge of the story to be served. The upper deck consists of a fixed platform and a vertically displaceable platform. Actuators supported on the fixed platform move the displaceable platform up and down until the upper platform is disposed flush with the upper edge of the story to be served, wherein positioning sensors control the movement of the platform. This allows both decks to be aligned with the respective stories.
A disadvantage of such known equipment resides in the fact that a movable platform driven at four corners can tilt. An offset can thereby arise between the platform and the story, which represents a significant risk of accident for boarding and alighting lift passengers.